Lockheed Martin – Space Fence Ground-Based S-Band Radar System Overview
HOW TO KEEP SPACE SAFE
Space Fence Solution
Construction is underway on Kwajalein Atoll in the Marshall Islands to build Space Fence, a sophisticated system that will dramatically improve the way the U.S. Air Force identifies and tracks objects in space. The new system’s initial operational capability is scheduled for 2018.
Gallium nitride (GaN) is a binary III/V direct bandgap semiconductor commonly used in bright light-emitting diodes since the 1990s. The compound is a very hard material that has a Wurtzite crystal structure. Its wide band gap of 3.4 eV affords it special properties for applications in optoelectronic, high-power and high-frequency devices. For example, GaN is the substrate which makes violet (405 nm) laser diodes possible, without use of nonlinear optical frequency-doubling.
Its sensitivity to ionizing radiation is low (like other group III nitrides), making it a suitable material for solar cell arrays for satellites. Military and space applications could also benefit as devices have shown stability in radiation environments. Because GaN transistors can operate at much higher temperatures and work at much higher voltages than gallium arsenide (GaAs) transistors, they make ideal power amplifiers at microwave frequencies.
Dr. Steven Greer : Star Wars is about Killing ETs